Jennifer Lopez reunites with former flame Diddy on 'American Idol,' Phillips, Sanchez dazzle

It was “oldies” night on “American Idol” Wednesday -- at least as far as the contestants were concerned. The gang tackled the music of Billy Joel, whose last major hit was in 1989 -- almost a decade before the youngest hopeful was born.

The Top Ten also received much-ignored fashion advice from a gray-haired–Tommy Hilfiger, and “mentoring” from a forty-something Sean “Diddy” Combs.

Judge Jennifer Lopez accidentally called Combs “Puffy” at one point, reminding everyone, except possibly the young finalists, of their turbulent, late ‘90s relationship.

Phillip Phillips, for one, was not about to take any old fogey’s advice.

“I’m just, like, a simple kind of guy,” Phillips told Hilfiger, after being advised that he needed some “help” with his style. “I want to bring the music first.”

Hilfiger went on to suggest that Phillips not wear gray on stage, as he deemed it to be “drab,” “boring,” and “dull.”

During his “mentoring” session with Jimmy Iovine and Combs, Phillips looked uncomfortable, not seeming particularly happy about Combs’ suggestion to ditch his beloved guitar and sing for an unnamed quartet of lithesome girls.

“Had a weird mentor session today but looking forward to next week,” Phillips tweeted on March 16.

Phillips answered his critics by wearing not one, but two, gray shirts on Wednesday and growling a stripped-down version of “Moving Out” with his guitar.

“I felt like you were taking out a little bit of aggression at the end of that -- maybe on your mentors,” laughed Lopez, before praising Phillips’ performance. “It was a perfect rendition of that song.”

Judge Randy Jackson called it “one of the best renditions of that song ever,” while judge Steven Tyler raved, “you took that song and you Phillip Phillips-ed that.”

Elise Testone, continuing to build on her strong performance last week, confidently sang a smokey, bluesy version of Joel’s 1977 hit, “Vienna.”

Tyler, in his usual understatement, said Testone's performance was "fantastic,” “brilliant” and “beautiful."

"It was such a beautiful thing," praised Lopez. "I really feel like everybody got to see your personality for the first time."

Judge Randy Jackson called Testone "unbelievably talented," saying that she had an elusive “moment” on the show. “That run at the end is so difficult, I don't know any singers that could probably sing that other than you."

Once again, Jessica Sanchez blew away the judges with her version of Joel’s “Everybody Has a Dream” from 1977’s “The Stranger,” while Colton Dixon closed the show with “Piano Man,” which gave Lopez “goosies from head to toe.”

If teenage girls weren’t responsible for the majority of votes on “American Idol,” HeeJun Han almost certainly would be going home Thursday based on his goofy performance of Joel’s “My Life.”

“Are you happy that you took the piss out of that song?” a visibly angry Tyler asked Han.  “The music business will kick your ass. At some point, you gotta try and take it a bit more serious.”

Next up: A singer from the Top Ten is voted off.